Conventional luggage is generally provided with a pull rod and a plurality of casters to facilitate the moving of the luggage. The pull rod and the casters of conventional luggage are fastened fixedly with the frame or shell of the luggages at the time when the luggage is made in the factory. In view of the fact that an additional space is often needed for the pull rod and the casters, a relatively large space for storage or shipment of the conventional luggage is often called for, thereby resulting in an increase in the cost of doing business.